The qemuDomainHasHotpluggableStartupVcpus() function is declared
to return an int but in fact its return type is a boolean. Even
its only caller (qemuProcessLaunch()) treats its retval as a
boolean. Switch the return type from integer to boolean.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Peter Krempa <pkrempa@redhat.com>